TR201807970T4 - Coated steel strip or sheet with advantageous properties. - Google Patents

Abstract

The invention relates to a strip or sheet of cold-formed cold-rolled steel coated with a zinc alloy layer, wherein the zinc alloy layer comprises 0.3 - 5 wt% Al and 0.3 - 5 wt% Mg, the remainder being zinc and unavoidable impurities and optional Pb, Sb, Ti, Ca, Mn, Sn, La, Ce, Cr, Ni, Zr, Bi, Si and Fe. the alloy layer is coated with a siloxane or polysiloxane layer, the siloxane or polysiloxane layer having a layer thickness compatible with 1 - 10 mg / m 2 Si. The invention also relates to a method of producing such a strip or sheet, a method of producing a strip or sheet of such a strip and a product produced from such a strip.

Description

DESCRIPTION COVERED STEEL STRIP WITH ADVANTAGEOUS FEATURES OR The invention is coated with a zinc alloy layer containing aluminum and magnesium. with a strip or plate of cold rolled steel that can be cold formed is relevant. The invention also allows the production of such a steel strip or plate. a method for producing a piece of strip or plate relates to a method and a product containing a part made of steel strip or plate.

Steel strip and sheet coated with a zinc or zinc alloy layer are well known and It is often used in the automotive industry. In recent years, aluminum and magnesium zinc alloy coatings, often galvanized or galvanized annealed coatings taking into account the improved corrosion and wear resistance compared to used. These zinc alloy layers are often 03 - 5% by weight A1 and depending on the group containing Pb, Sb, Ti, Ca, Mn, Sn, La, Ce, Cr, Ni, Zr, Bi, Si and Fe. to a total of not more than 0.2% by weight of one or more selected additional elements corresponds to.

However, this aluminum and magnesium-containing zinc-coated steel adhesive joint of normal hot-dip zinc-coated steel It has a disadvantage in that it is less. Also, hot-dip Spot weldability of coatings is often found in electrogalvanized steel. less than it is. In addition, zinc with aluminum and magnesium coatings partially have higher friction than normal zinc coatings. has a coefficient.

An aluminum and magnesium-containing product with good adhesive bonding properties. It is a part of the invention to provide a steel strip or sheet coated with a zinc alloy layer. is the purpose. 00453-P-0016 Aluminum and magnesium with good spot weldability To provide a steel strip or sheet coated with a zinc alloy layer containing is another purpose of the invention.

An aluminum and magnesium-containing product with an improved coefficient of friction. provide a steel strip or sheet coated with a zinc alloy layer. is another purpose.

In addition, it is coated with a zinc alloy layer containing aluminum and magnesium. to provide a method for producing such a steel strip or plate is another purpose of the invention.

Also, according to the invention, it is possible to produce a part from such a steel strip or plate. It is another object of the invention to provide a method for In addition, steel strip according to the invention with good joining properties between parts a product manufactured from a part made of or plate and at least one other part According to a first aspect of the invention, one or more of these articles is a zinc cold rolled, which can be cold formed, coated with a layer of alloy obtained by a strip or plate of steel, wherein the zinc alloy layer Contains 03 - 5 wt% A1 and 03 - 5 wt% Mg, the remainder being zinc and are inevitable impurities and optionally Pb, Sb, Ti, Ca, Mn, Sn, La, Ce, One or more additional elements selected from the group consisting of Cr, Ni, Zr, Bi, Si and Fe totals at most 0.2% by weight, where the zinc alloy layer coated with a layer of siloxane or polysiloxane, siloxane or polysiloxane layer has a layer thickness corresponding to 1 - 10 mg/m2 Si.

Inventors, as noted above, with a layer of siloxane or polysiloxane. Such a layer of bonding behavior of steel coated with zinc alloy, especially 00453-P-0016 adhesive joint behavior, but also without spot weldability surprisingly, he found it to be better than the coalescing behavior. A steel coated with a zinc alloy provided with a siloxane or polysiloxane layer The strength and failure mode of the joints connected with the adhesive, such a steel coated with zinc alloy without siloxane or polysiloxane layer better than it is. In addition, friction of steel coated with zinc alloy, for example siloxane or polysiloxane which is advantageous for deep drawing processes is reduced by at least 10% through the application of the layer. siloxane or polysiloxane The behavior of steel coated with zinc alloy with a layer of at least frictional adhesion of material without such a layer as good as his behavior. Zinc coated with a siloxane or polysiloxane layer Phosphate coating of alloy coated steel, siloxane or polysiloxane layer It is as good as the phosphate coating of steel coated with zinc alloy, which does not have

Siloxane to improve adhesive bonding of aluminum parts or polyoxane is known, but zinc or zinc alloy coated steel siloxane for improving the adhesive bonding of parts or The use of polysiloxane is unknown. Siloxane on zinc coated steels or polysiloxane to improve corrosion resistance and lacquer adhesion properties. well known, but spot welding and phosphate forming for automotive purposes is not an option due to its limitations. US 5,433,976 coated with siloxane A1 with a zinc alloy coating containing magnesium and aluminum describes a hot-dip galvanized cold-rolled steel strip coated. According to an unpublished patent application, a siloxane or polysiloxane an oxidation of the zinc layer during the hot forming process. hot forming, resulting in a reduction in zinc and a reduction in zinc losses. steel strip, sheet or blank coated with a zinc or zinc alloy used on. According to former patent practice siloxane or polysiloxane, this So it is used for a different type of steel and a different process. The present invention 00453-P-0016 on the contrary, for hot forming at a temperature of 600°C or more. with cold rolled steel that can be cold formed, which is not a steel According to a preferred embodiment, the cold rolled steel has the following weight A1<0.5 the rest are Fe and inevitable impurities. A composition within these ranges steel types are generally used for processes that can be cold formed.

Preferably, Arayer Free steel (IF-steel) is an oven-proof steel or a dual-phase steel. Steel strip or plate, such as steel (DP steel), has a tensile strength of up to 600 MPa. has strength. This type of steel is intended for parts connecting to other parts. It is often used in the automotive industry.

According to a preferred embodiment, the zinc alloy layer on the steel is It has a thickness of 20 - 140 g/mz on the side. These zinc alloy thicknesses It is often used in the automotive industry for steel. 00453-P-0016 Preferably, the siloxane or polysiloxane layer is compatible with 1 to 8 mg/m2 of Si. layer thickness, preferably 1 - 5 rng/m2 Si. This is reduced It has been found that advantages are obtained with thicknesses, on the other hand, it is an economical From the point of view, it is preferable to use thin layers.

According to a preferred embodiment. siloxane or polysiloxane layer from tri(m)ethoxysilylalkane, preferably a bis-triethoxysilylethane (BTSE), and preferably y-aminopropyltriethoxysilane (yAPS), bis-aminosilane (BAS), bis-diaminosilane (BDAS), vinyltriacetoxysilane (VTAS), y-ureidopropyltrimethoxysilane (yUPS) and/or combination with another silane such as bis-trimethoxysilylpropylurea (BUPS) created in. These silane chemicals are suitable for steel coated with a zinc alloy. as a relatively easy-to-apply water-based solution on strip or board can be used. In water, silane chemicals are hydrolyzed to form silanols. will be.

According to a preferred embodiment, the zinc alloy layer is 1.0 to 3.5 wt% A1 and 1.0 - 3.5 wt% Mg, preferably 1.4 - 2.2 wt% A1 and 1.4 wt% - Contains 2.2 Mg. These amounts of A1 and Mg in the zinc layer are generally found in automotive It provides corrosion protection that may be suitable for other purposes. Higher quantities, zinc alloy is comparatively more expensive and more welded makes it difficult.

Preferably, the siloxane or polysiloxane layer is coated with an oil. Zinc or Zinc alloy coated strip is usually not supplied to the automotive industry. It is provided with a thin layer of oil first.

According to a second aspect of the invention, a strip or plate is made according to the first aspect of the invention. A method for producing it is provided in accordance with claim 9. In this way, the siloxane or polysiloxane layer in steel series coated with zinc alloy or it is relatively easy to apply to the board in an environmentally friendly way. 00453-P-0016 Preferably, the water-based solution containing silane/silanol is a fluoride, preferably hydrogen fluoride, Contains horosiliconic acid, Ilorozibonic acid and/or fluorotitanic acid. Such fluorides, Zinc alloy on steel strip or sheet of siloxane or polysiloxane layer is added to the layer to improve its stickiness.

According to a third aspect of the invention, cold rolled steel coated with a zinc alloy a part of steel strip or plate, according to a first aspect of the invention, of siloxane or A method for producing the polysiloxane layer is provided, wherein - cut from a strip or sheet of bare metal - the blank is placed in a forming tool such as a press - The raw inetale is cold shaped as a piece.

Using this method, the friction of the blank against the forming tool decreases due to the presence of siloxane or polysiloxane layer. This is a sequel for all plates that are cold formed using the extrusion tool and the same high-strength, which suffers from insufficient poor tensile properties at the same time It is advantageous for the use of steels.

According to a fourth aspect of the invention, according to the first aspect of the invention, lane or a piece made of sheet metal and one or more other pieces product is supplied, where the part is made of strip or plate spot welding and/or with at least one of the other parts using a sealant or adhesive. are combined. The bonding is improved due to the siloxane or polysiloxane layer.

Preferably, one or more other parts are a strip according to the first aspect of the invention. or made of sheet. These parts are made of steel strip or plate coated with zinc alloy. well provided by the siloxane or polysiloxane layer provided on provides a product with bonding properties. An added advantage is the improved raw metals cut from steel strip or plate due to the coefficient of friction It is an improved cold forming feature. 00453-P-0016 According to a preferred embodiment, the product consists of a phosphate layer followed by a It is provided with a painting layer. For automotive purposes, here the product is a vehicle. part, the car is usually good for applying a paint layer. It is cleaned with alkaline or coated with phosphate to provide an adhesion. good morning my baby a good crystalline, non-porous phosphate of an adhesive zinc alloy layer A good electrochemical treatment with the phosphate solution to result in a layer of zinc alloy coating only, as it is necessary to react will be achieved when it is not blocked by remaining surface contaminants.

A good phosphate layer of the applied siloxane or polysiloxane layer It has been found that its creation cannot be prevented.

The invention will be described with reference to the following non-limiting examples.

Figure 1 with or without a siloxane or polysiloxane layer It shows the frictional behavior of steels coated with zinc alloy without

Figure 2, with or without a siloxane or polysiloxane layer It shows the paint layer separation of the zinc alloy steel painted without

Experiments have been carried out, where the steel strip coated with a zinc alloy has two different coated with a thick layer of siloxane or polysiloxane. In this way samples of the coated sheets without a siloxane or polysiloxane layer Tested and compared with zinc alloy coated plate.

Two types of steel plates were used for the experiments. Steel grade (1) 0.7 mm caliber is a cold rolled boron steel. Steel grade (2) 0.7 It was a cold rolled ductile steel with a caliber of mm.

ZnAlMg coating on both steel types, coating thickness nitrogen up to about 70 mg/m2 on both sides (approximately both sides) by wiping 10 µm on the side) in a continuous hot dip galvanizing production applied to the line. Coating composition, hot dip galvanizing (approx. 00453-P-0016 Reaction of aluminum with steel strip during 0.005% - 0.02 wt% Fe) with a small amount of Fe via approximately 1.6 wt% A1 and steel, with Electrical Discharge Texture (EDT) roughness of approx. Containing both bis-triethoxysilylethane (BTSE) and aminopropyltriethoxysilane (APS) a water-based solution, after drying and/or curing, 2 and 12, respectively to provide a (poly)siloxane layer with a thickness of mg/m2 Si. It was applied on the steel coated with ZnAlMg with a chemical coater.

In the remainder of the description, both the siloxane layer and the polysiloxane layer Samples for the ply shear test follow the StahlEisen SEP 1160 Teil 5 procedure. prepared according to: i Size of steel coupons: 100 mm x 25 mm 0 Cleaning: Degreased by US in heptane for 10 minutes . Oil application (if applied): 2 g/m2 MULTIDRAW PL61 Zeller&Gmelin (standard automotive Pre-lubrication) - Cross section: 10 mm - Adhesive thickness: 0.2 to 0.3 mm, controlled using glass beads has been . Excess adhesive removed before curing o Curing: 15 minutes at 180°C object temperature 0 Test length: 110 mm 0 Test speed: 10 mm/min.

The adhesive used was Betamate 1496V from DOW Chemical. Some After the samples have been cleaned to separately evaluate the interaction with the oil, 00453-P-0016 then it is not re-oiled. In general, the oil will be absorbed by the adhesive, makes it a little weaker.

The strength upon failure of the joint is given in Table 1. This strength depends heavily on the grade of steel and its caliber and only can be compared with the reference sample. The connection is the preferred failure mode. may break inside the adhesive (glue failure). Also, sticky and metallic between coating (adhesive failure), this is less desirable. Often, the broken link shows a combination of both failure modes and each The amount of tahini (in % for the cut area) is visually tahini.

The results (see Table 1) have a thin (2 mg/in2 Si) siloxane layer. Both strength and failure mode of steel coated with ZnAlMg, siloxane shows that it is better than steel coated with ZnAlMg without #1 against reference3 and #2 against reference4 and #3) against reference4. best complaint mode is achieved for oily conditions.

With Si >10 mg/m2, there is no improvement in the thickness of the siloxane layer, on the contrary (see #1 against referenceZ), but a little sticky at this point claim is obtained.

Table 1: adhesive properties Steel Silane Oil Strength Standard % % type (mg/m2) (front connection (kN) deflection adhesive adhesive 00453-P-0016 Steel Silane Oil Strength Standard % % type (mg/m2) (front connection (kN) deflection adhesive adhesive Steel (steel grade 2) coated with ZnAlMg coated with siloxane (2 mg/m2 Si) friction and frictional adhesion, also in a Linear Friction Test has been evaluated.

The test is a flat instrument to develop a high-pressure contact with the specimen surfaces. and uses a round tool. The tool material used is DIN 1.3343. samples 1 g/m2 Multidraw PL61 oil from Zeller & Gmelinprelube is applied.

For each material/lubrication system, 50 mm wide and 300 mm long strips a series of tools pulled together with a normal force of 5 kN was taken at a speed of 20 mm/min. The strips have a test distance of 55mm taken six times (pass) with tools throughout; after each blow, the tools has been released and the strips are in the original to prepare for the next blow. returned to the starting position. All tests were done at 20°C and three times has been carried out.

Figure 1 shows the number of passes on the horizontal axis and the number of passes on the vertical axis. shows the coefficient of friction. Continuous line, testing for a siloxane coating shows results, interrupted line results without siloxane coating shows. The results in Figure 1 show that the thin siloxane layer reduces friction. indicates, this means a better pulling behavior. Normally good and warm dip zinc coated steel, electro galvanized steel and galvanized annealed steel 00453-P-0016 The frictional adhesion behavior of steel coated with ZnAlMg, which is better than steel, is It's much better on point. Samples with a size of 100x200 mm are prepared in a standard automotive alkaline Cleaner, activation and Chemetall phosphate according to automotive standards coated with phosphate. The amount of phosphate released was determined (measured via) and the crystal size and homogeneity were checked (secondary electron by microscopy).

The results can be found in Table 2. All results are good and siloxanine is fine the presence of katinanin is combined with a siloxane layer having a thickness of 12 mg/m2. on the phosphate-ability of the supplied steel grade (1), except for the phosphate-ability did not have a negative effect.

Table 2: Coating with Phosphate Steel Silane genus (mg/m2) reference l 0 reference2 1 12 reference3 2 0 Phosphate type Quantity (Chemetall) phosphate 100 - 200 ppm F with Sprayphosphate GB 3.3 R2830E3 100 - 200 ppm F with Sprayphosphate GB 2,4 R2830E3 100 - 200 ppm F with Sprayphosphate GB 3,5 R2830E3 2 6 with GB R2600 dipped phosphate, phosphate crystal size and homogeneity Not good 00453-P-0016 Type of Steel Silane Phosphate Quantity Phosphate crystal type (mg/m2) (Chemetall) phosphate size and type (g/m2) homogeneity With GB R2600, . dipped phosphate For testing spot welding behavior, weld range siloxane according to StahlEisen SEP 1220 Teil 2 for a sample without and steel a sample with a thin layer of siloxane (2 mg/m2 Si) above the type (2). determined in duplicate. A standard pre-oil (1 g/m2 Quaker N6130) was applied to all samples.

Weld gap, current required to achieve minimum weld fill (lm) and maximum current before jumping occurs during welding (lmax). A wider weld range, a better electrode life, of replacing an electrode to get a good weld. It is a strong indicator of the number of resources before they are needed.

Minimum and maximum source currents and source spacing are given in Table 3.

Welding range of silane (#2 and #3) and ZnAlMg coating, silane (reference3) is greater than the welding gap on the same samples without

Table 3: Source range Steel grade Silane (mg/m2) lmin (kA) Imax (kA) Range (kA) 00453-P-0016 Phosphated samples (references 3 and #2 from Table 2) are intended for the following tests. Additional E-coated with 20-25 µm Cathoguard 500 from BASF: For a corrosion test, with a Van Laar pen (double) of panels There are scratches up to the steel on it. Panels according to VDA 621-415 It has been subjected to a weekly accelerated cyclic corrosion test. Paint layer separation was evaluated according to Volvo STD 1029.

For an E-coating bonding, test panels cross cover pattern (6 vertical, 6 horizontal, Gitterschnitt) and an Andreas Cross (inside steel).

These panels were first put in a humidity test according to GMW 14829 for 120 hours and checked for layer separation along scratches. After that, 300 - Made according to 3: 2003 (E).

Corrosion results can be found in Figure 2. Above the vertical axis, corrosion The delamination of the E-coating after testing is given in millimeters.

Samples with a siloxane layer, denoted by A, with a siloxane layer Samples that do not exist are denoted by B. Visible layer separation, with white bar are indicated, visible plus invisible layer separation is indicated by a dark bar.

The variability in terms of layer separation is shown in the figure. As can be seen, Corrosion of steel coated with ZnAlMg with and without a siloxane layer. The difference in resistance is small.

E-coat adhesion was good after moisture test (layer separation none). The results after the water immersion test are given in Table 4. with siloxane the results of the treated sample and the reference were almost identical. 00453-P-0016 Table 4: E-coating bonding after water immersion test Cross hatch Andreas cross Size Quantity Size Quantity with siloxane 3 5 3 3 Without siloxane 3-4 5 3 4 00453-P-0016 0.1 7 ,

Claims (2)

CLAIM 1. A cold formed cold rolled strip or sheet coated with a layer of zinc alloy, where the zinc alloy layer contains 03 - 5% by weight A1 and 03 - 5% by weight Mg, the remainder being zinc and inevitable impurities and optionally Pb, One or more additional elements selected from the group consisting of Sb, Ti, Ca, Mn, Sn, La, Ce, Cr, Ni, Zr, Bi, Si and Fe corresponds to a total of at most 0.2% by weight, where the zinc alloy layer is a coated with a siloxane or polysiloxane layer, the siloxane or polysiloxane layer has a layer thickness compatible with 1 - 10 mg/m2 Si. 2. Strip or Sheet according to claim I, wherein the cold rolled steel has a composition with the following % by weight: A1<0.5 the remainder is Fe and inevitable impurities. . Strip or plate according to Istein 1 or 2, wherein steel such as an Arayer Free steel (IF-steel), a bakable steel or a dual-phase steel (DP steel) has a tensile strength of up to 600 MPa. . Strip or plate according to claim 1, 2 or 3, wherein the zinc alloy layer on the steel has a thickness of 20 - 140 g/mz on both sides. . Strip or sheet according to any preceding claim, wherein the siloxane or polysiloxane layer has a layer thickness compatible with 1 - 8 mg/m2 Si, preferably 1 - 5 mg/m2 Si. . A strip or sheet according to any preceding claim, wherein the siloxane or polysiloxane layer is made of a bis-tri(m)ethoxysilylalkane, preferably a bis-triethoxysilylethane (BTSE), and preferably y-aminopropyltriethoxysilane (yAPS), bis-aminosilane (BAS), bis- It was formed in combination with another silane such as diaminosilane (BDAS), vinyltriacetoxysilane (VTAS), y-ureidopropyltrimethoxysilane (yUPS) and/or bis-trimethoxysilylpropylurea (BUPS). . Strip or sheet according to any one of the preceding claims, wherein the zinc alloy layer is 1.0 - 3.5% by weight A1 and 1.0 - 3.5% by weight Mg, preferably 1.4 - 2.2 wt.% A1 and 1.4 - 2% by weight. Contains 2 Mg. . Strip or sheet according to any preceding claim, wherein the siloxane or polysiloxane layer is coated with an oil. . A method for producing strip or sheet according to any one of the preceding claims, wherein the siloxane or polysiloxane layer is a water-based solution containing a silane/silanol applied by dipping and/or spraying the zinc alloy layer with additional squeezing or rolling, followed by drying and/or curing. It is created by supplying with. 10. The method of claim 9, wherein the silane/silanol containing water-based solution contains a fluoride, preferably hydrogen fluoride, fluorosilicic acid, fluorosiric acid and/or fluorotitanic acid. ll. Method for producing a piece from a strip or sheet according to any one of claims 1 to 8, wherein a blank is cut from the strip or sheet. 10 - the blank is placed in a forming tool such as a press - the blank is cold formed as a piece. 12. Product manufactured from a piece of strip or plate and one or more pieces according to any one of claims 1 to 8, wherein the piece of strip 15 or plate is joined to at least one other piece using spot welding and/or sealant or adhesive . 13. The article of claim 12, wherein one or more other parts are made of a strip or plate according to any one of claims 1-8. The product according to claim 12 or 13, wherein the product is provided with a phosphate layer followed by a dyeing layer.